. . . . "the outer region of the Earth's atmosphere; contains a high concentration of free electrons"@en-us . "0"^^ . . . . . . "ionosphere"@en-us . . . . "the outer region of the Earth's atmosphere; contains a high concentration of free electrons"@en-us . "108588916"^^ . . "08588916-n"^^ . . . "ionosphere"^^ . "108064332"@en-us . . "0"^^ .